Ochi's approach solves the heterogenous vehicleroutingproblem using the constraint having fixed costs as a multiplier of residuals. However, in this approach, there is not any information about which vehicle wil...
详细信息
Ochi's approach solves the heterogenous vehicleroutingproblem using the constraint having fixed costs as a multiplier of residuals. However, in this approach, there is not any information about which vehicle will be assigned to the route related to this constraint. In our study, Ochi's approach is interpreted again in terms of vehicle capacity and number of customers assigned to each route. The proposed routing approach is taking the higher capacity vehicle for improving the performance. Then the solution phases of a sample problem are shown by using the given algorithm. In order to highlight the performance of the routing approach, Golden's 12 test problems (fleet size and mix vehicle routing problem with Fixed Cost) are used. It is seen that the proposed method has better average time complexity and equal cost performances than Ochi's routing approach. Therefore, the solutions with higher capacity vehicle of the proposed method that uses vehicle type information are better than those of the methods that use residual cost based on the vehicle type information.
This paper studies the fleet size and mix vehicle routing problem (FSMVRP), in which the fleet is heterogeneous and its composition to be determined. We design and implement a genetic algorithm (CA) based heuristic. O...
详细信息
This paper studies the fleet size and mix vehicle routing problem (FSMVRP), in which the fleet is heterogeneous and its composition to be determined. We design and implement a genetic algorithm (CA) based heuristic. On a set of twenty benchmark problems it reaches the best-known solution 14 times and finds one new best solution. It also provides a competitive performance in terms of average solution. (C) 2008 Elsevier Ltd. All rights reserved.
To balance a fragmented logistics organization, Small and Medium Enterprises have to find collective solutions to decrease their environmental impact. Especially when the demand at each producer takes the form of smal...
详细信息
ISBN:
(纸本)9783662447352
To balance a fragmented logistics organization, Small and Medium Enterprises have to find collective solutions to decrease their environmental impact. Especially when the demand at each producer takes the form of small packages and low quantities this paper examines the effect of the introduction of a consolidation center on the environmental issue. Therefore, the fleet size and mix vehicle routing problem (FSMVRP) was adapted in order to minimize CO2 emission. An exact mathematical formulation of the extended problem was developed to investigate the difference between homogeneous and heterogeneous fleetsize on the environmental issue. Computational experiments for the problem formulation are performed using CPLEX and give a solution of a small instance to illustrate the problem. A case study focuses on optimal parcel picking up, from many producers to a common depot in the agri-food sector.
This paper presents a continuous approximation model to determine the long-term vehiclefleet composition needed to perform distribution activities. The problem is a realistic variant of the vehicleroutingproblem, i...
详细信息
This paper presents a continuous approximation model to determine the long-term vehiclefleet composition needed to perform distribution activities. The problem is a realistic variant of the vehicleroutingproblem, in which the fleetsize and mix are also decision variables. The types of vehicles differ in terms of their capacities, fixed costs and variable costs. The objective is to minimize the total cost, subject to capacity and route duration constraints. We assume customers are distributed over a circular service region partitioned into zones, each of which is serviced by a single vehicle. The routing costs are assessed through a continuous approximation model. We present a mixed integer non-linear formulation for the problem, followed by computationally efficient upper and lower bounding procedures. The performance of the model and of its bounds is assessed on several test instances. (C) 2012 Elsevier Ltd. All rights reserved.
The paper addresses the fleetsize and mix door-to-airport problem (FSMDAP) in flight ticket sales companies in China. The problem is formulated under the framework of the fleet size and mix vehicle routing problem wi...
详细信息
The paper addresses the fleetsize and mix door-to-airport problem (FSMDAP) in flight ticket sales companies in China. The problem is formulated under the framework of the fleet size and mix vehicle routing problem with time windows (FSMVRPTW). A mixed integer programming model is presented, and service quality is factored in constraints, by introducing passenger satisfaction degree functions that consider time window and ride time. A new saving-based insertion algorithm is then performed until no more improvement is found. The approaches are evaluated based on optimal solutions by using an exact Set Partition algorithm of enumerating all routes for 51 small problems. It is shown that the approaches are capable of generating near-optimal solutions very quickly for randomly generated instances with up to 50 requests.
暂无评论